通常转子轴上的疲劳裂纹为椭圆形尖端，而国内外现有文献大多关注直裂纹转子，很少对椭圆裂纹呼吸行为建立模型。提出了新的圆柱轴椭圆裂纹呼吸模型，修正中性轴位置确定裂纹张开面积，并基于裂纹应变能计算出椭圆裂纹附加柔性系数，建立了该类裂纹转子弯曲刚度模型。进一步，与文献和有限元结果进行对比，裂纹呼吸规律完全符合，裂纹附加柔度、转子无量纲挠度满足计算要求，验证了该模型有效可行。
Abstract
Usually the fatigue crack on shaft of rotor is with an elliptical tip, while the existing literatures at home and abroad mostly focus on straight-tip crack rotor, rarely on elliptical-tip crack breathing behavior. A new breathing model of elliptical crack in cylindrical shaft that modifying neutral axis’s position simulates crack open area is proposed, and based on the crack strain cracked additional flexibility coefficient is calculated, and a stiffness model of elliptical cracked rotor under bending is also established. Further, compared with the literatures and the finite element results, the proposed crack breathing laws agree completely, and cracked additional flexibility and rotor’s dimensionless deflection both meet precision of computing. Thus the model is validated.
关键词
裂纹转子 /
椭圆裂纹 /
呼吸性 /
弯曲刚度
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Key words
cracked rotor /
elliptical crack /
breathing mechanism /
bending stiffness
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参考文献
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